Sistemas adesivos simplificados contendo nanopartículas de zinco e cobre: estudo in vitro

Abstract

Objectives: To evaluate the effects of adding different concentrations of zinc and copper nanoparticles (NP) in two different simplified adhesive systems in maximum tensile strength (MTBS), degree of conversion (DC), sorption (SO) and solubility (SB). Methodologies: Prior to inclusion, nanoparticles were characterized by atomic force microscopy (AFM), zeta potential, field effect scanning electron microscopy (FEG) and X-ray dispersive energy spectroscopy (EDS). The NP were added to the adhesive systems Ambar (AMB) and Ambar with APS (APS) (FGM) in the concentrations: 0% (control); 5% zinc + 0.1% copper; 5% zinc + 0.2% copper and 10% zinc + 0.1% copper by weight. For RMT, 10 adhesive specimens (CP) were made for each concentration using a metallic matrix. Half (n = 5) was tested immediately (IM) and the other half (n = 5) after 28 days of storage in water. For GC (n = 3 per group), adhesive discs (n = 3 for each group) were made in a metallic matrix (5.8 mm x 1.0 mm) and the reading was made using micro-Raman spectrometry. For SO and SB, the same GC matrix was used (n = 10) and the specimens were weighed in 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 24h, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 14 days and 28 days with storage in distilled water. RMT data were analyzed by a 3-factor analysis of variance. For CG, data were analyzed by analysis of variance of two. For SO and SB, the 28-day data were analyzed by two-way analysis of variance and the Tukey test for multiple comparisons. Results: Characterization analyzes showed results consistent with nanoparticle size and particle purity for zinc and copper. RMT showed better results after 28 days for both groups. The inclusion of NP did not change the GC to AMB but reduced to PHC. In SO and SB the inclusion of PN did not change the values in relation to the control groups. Conclusion: The inclusion of zinc and copper nanoparticles in combination may be a viable alternative the best performance of adhesive systems.